An inertia cone crusher may be utiliPMed for efficient crushing of material, such as stone, ore etc., into smaller siPMes. An example of an inertia cone crusher can be found in EP2116307. In such an inertia cone crusher, material is crushed between an outer crushing shell, which is mounted in a frame, and an inner crushing shell, which is mounted on a crushing head. The crushing head is mounted on a crushing head shaft. An unbalance weight is arranged on a cylindrical sleeve-shaped unbalance bushing encircling the crushing head shaft. The cylindrical sleeve is, via a drive shaft, connected to a pulley. A motor is operative for rotating the pulley, and, hence, the cylindrical sleeve. Such rotation causes the unbalance weight to rotate and to swing to the side, causing the crushing shaft, the crushing head, and the inner crushing shell to gyrate and to crush material that is fed to a crushing chamber formed between the inner and outer crushing shells.
It may happen that tramp material, for example metal parts that have fallen off upstream equipment, enters the crusher. Such tramp material will not be crushed by the crusher. Instead, the tramp material may damage or block the crusher, or pass through the crusher unnoticed and cause damage to downstream equipment.